:root {
  --bg: #0d1b2a;
  --panel: #14253a;
  --panel2: #1b3047;
  --ink: #e8eef5;
  --muted: #9fb3c8;
  --accent: #3b82f6;
  --accent2: #16a34a;
  --line: #26415e;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  background: var(--bg); color: var(--ink);
  font: 14px/1.45 system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  display: flex; flex-direction: column; min-height: 100vh;
}
header { padding: 14px 20px; border-bottom: 1px solid var(--line); }
header h1 { margin: 0; font-size: 20px; letter-spacing: .3px; }
header .sub { margin: 2px 0 0; color: var(--muted); font-size: 13px; }

main { flex: 1; display: grid; grid-template-columns: 340px 1fr; gap: 0; min-height: 0; }

.panel {
  background: var(--panel); border-right: 1px solid var(--line);
  padding: 14px; overflow-y: auto;
}
.panel h2 { font-size: 13px; text-transform: uppercase; letter-spacing: .6px; color: var(--muted); margin: 4px 0 10px; }
.panel section { margin-bottom: 22px; }

.grid { display: flex; flex-direction: column; gap: 9px; }
.ctl { display: grid; grid-template-columns: 1fr 110px; align-items: center; gap: 8px; }
.ctl label { color: var(--muted); font-size: 13px; }
.ctl input[type=number], .ctl select {
  background: var(--panel2); color: var(--ink); border: 1px solid var(--line);
  border-radius: 6px; padding: 6px 8px; width: 100%; font-size: 13px;
}
.ctl input[type=checkbox] { width: 18px; height: 18px; justify-self: start; }
.ctl input:focus, .ctl select:focus { outline: none; border-color: var(--accent); }

.tabs { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.tab {
  background: var(--panel2); color: var(--muted); border: 1px solid var(--line);
  border-radius: 999px; padding: 6px 12px; font-size: 13px; cursor: pointer;
}
.tab.active { background: var(--accent); color: #fff; border-color: var(--accent); }

.exports { display: flex; flex-direction: column; gap: 8px; }
.exports button {
  background: var(--panel2); color: var(--ink); border: 1px solid var(--line);
  border-radius: 8px; padding: 10px; font-size: 14px; cursor: pointer;
}
.exports button:hover { border-color: var(--accent); }
.exports .primary { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 600; }
.send-msg { color: var(--accent2); font-size: 12px; margin: 2px 0 0; min-height: 14px; }

.stage { display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 18px; min-width: 0; }
#preview {
  width: min(72vh, 100%); height: auto; aspect-ratio: 1/1;
  background: radial-gradient(circle at 50% 45%, #0f2236, #0a1622);
  border: 1px solid var(--line); border-radius: 12px;
}
.info { margin-top: 12px; color: var(--muted); font-size: 13px; text-align: center; max-width: 760px; }
.info b { color: var(--ink); font-weight: 600; }
.legend { color: var(--muted); font-size: 12px; margin-top: 6px; }
.legend .k { display: inline-block; width: 14px; height: 0; border-top: 3px solid; vertical-align: middle; margin-right: 3px; }
.legend .tex { border-color: #1d4ed8; }
.legend .od { border-color: #dc2626; }
.legend .pd { border-color: #16a34a; }

footer { padding: 10px 20px; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
footer code { background: var(--panel2); padding: 1px 5px; border-radius: 4px; }

@media (max-width: 800px) {
  main { grid-template-columns: 1fr; }
  .panel { border-right: none; border-bottom: 1px solid var(--line); }
}